腾讯云服务器Linux系统--安装MySql

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本文链接：https://blog.csdn.net/weixin_43126117/article/details/100840495

检查Linux服务器是否有Mysql

[root@VM_0_16_centos ~]# rpm -qa|grep mysql*
[root@VM_0_16_centos ~]# rpm -qa|grep -i mysql

如有，必须卸载干净，否则后面安装会报各种错误。

我们还是通过华为云镜像进行下载 MySql-Server、MySql-Client这两个服务，其他（开发库、兼容库、测试组件等）不安装。

创建目录，进入目录，并下载文件。

[root@VM_0_16_centos ~]# mkdir /usr/lib/mysql
[root@VM_0_16_centos ~]# cd /usr/lib/mysql

[root@VM_0_16_centos mysql]# wget https://mirrors.huaweicloud.com/mysql/Downloads/MySQL-8.0/mysql-community-server-8.0.16-2.el7.x86_64.rpm

[root@VM_0_16_centos mysql]# wget https://mirrors.huaweicloud.com/mysql/Downloads/MySQL-8.0/mysql-community-client-8.0.16-2.el7.x86_64.rpm

我安装的时候提示我需要两个服务，我就下载安装了。

[root@VM_0_16_centos mysql]# wget https://mirrors.huaweicloud.com/mysql/Downloads/MySQL-8.0/mysql-community-common-8.0.16-2.el7.x86_64.rpm
[root@VM_0_16_centos mysql]# wget https://mirrors.huaweicloud.com/mysql/Downloads/MySQL-8.0/mysql-community-libs-8.0.16-2.el7.x86_64.rpm

安装顺序如下：common>libs>server>client

注意的一点是，从 RPM 版本 4.1 开始，在安装或升级软件包时会检查软件包的签名。如果签名校验失败，你就会看到如下所示 的错误消息：

Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY

安装的时候需要取消校验签名 --force --nodeps

--force 　强行置换套件或文件。

--nodeps 　不验证套件档的相互关联性。

[root@VM_0_16_centos mysql]# rpm -ivh mysql-community-common-8.0.16-2.el7.x86_64.rpm 

[root@VM_0_16_centos mysql]# rpm -ivh mysql-community-libs-8.0.16-2.el7.x86_64.rpm --force --nodeps

[root@VM_0_16_centos mysql]# rpm -ivh mysql-community-server-8.0.16-2.el7.x86_64.rpm --force --nodeps

[root@VM_0_16_centos mysql]# rpm -ivh mysql-community-client-8.0.16-2.el7.x86_64.rpm 

安装完毕后，启动mysql服务

[root@VM_0_16_centos ~]# systemctl start mysqld

我启动的时候，报了很多错误。

所以给一个通用的解法：检查mysql服务的系统日志，看看报什么错。路径是什么呢？ 可以通过配置文件获取

[root@VM_0_16_centos ~]# cat /etc/my.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html

[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

# Disabling symbolic- s is recommended to prevent assorted security risks
symbolic- s=0

log-error=/var/log/mysqld.log                //日志路径
pid-file=/var/run/mysqld/mysqld.pid
datadir=/opt/data

skip-grant-tables

然后登陆MySQL，并修改密码

通过 grep "password" /var/log/mysqld.log ，取得mysql初始化随机密码，但是我这里不可以。

只能通过修改配置文件，进入无保护状态下的MySQL。

[root@VM_0_16_centos ~]# vi /etc/my.cnf 

//加上
    skip-grant-tables
//重启
[root@VM_0_16_centos ~]# systemctl restart mysqld
//无密码进入
[root@VM_0_16_centos ~]# mysql -uroot -p

use mysql；
UPDATE user SET authentication_string = Password ('密码') WHERE User = 'root' ;
flush privileges ; 

quit；

//删除/etc/my.cnf 中 skip-grant-tables
//重启

再次通过刚刚设置的密码进入系统，可能还要重新设置密码，刚刚设置的好像只是临时的

SET PASSWORD = PASSWORD('!Qw56:');   //密码需要很复杂，否则报错
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

//设置密码为永久
ALTER USER 'root'@'localhost' PASSWORD EXPIRE NEVER; 
//设置外部可以访问
grant all privileges on *.* to root@"%" identified by "!Qw56:";
//更新
flush privileges; 

还需要开放云服务器安全组的端口。